Vapor electric device



Sept l0, 1940- H. A. ROSE l 2,214,596

VAPOR ELECTRIC DEVICE www' Ff- ATTORNEY sept. ro, 1s40. H. A. Rose2,214,596

VAPOR ELECTRIC DEVICE ATTORNEY Patented Sept. 10,1940

PATENT OFFICE VAPOR ELECTRIC DEVICE Herbert A. Rose, Leonia, N. J.,assigner to Westinghouse Electric & Manufacturing Company, EastPittsburgh, Pa., a corporation of Penn- Sylvania Application April 14:,1938, Serial No.- 201,955

2 Claims.

operation of the device has in part been responsible for thesedisturbances.

According to my invention, I have provided a shield interposed betweenthe anode and the cooled condensing surfaces so that the anode will notbe directly exposed to a cooled surface, and further the shield is sopositioned that any material thrown off or evaporated from thecondensing surface will be separated lfrom the im- 20 mediate anodechamber. I have accomplished this by providing a shield intermediate theanode and the condensing surface. The shield, being in partial vacuum,is thermally insulated so that in `operation of the device it assumes atemperature intermediate between that of the anode and the condensingsurface, but nearer that of the anode. As vapor electric devicesoperatel in a-highly evacuated state, substantially all of the heattransferred from the anode must be transferred by radiation.Consequently, the heat received by the shield must be received byradiation and likewise disposed of by radiation. The shield thereforeincreases to a temperature determined by the radiant energy falling uponit and the area of its own radiating envelope exposed to other externalenergy absorbing surfaces, the cooled Walls of the tube constituting theprincipal energy absorbing elem-ent. Positive ions also raise thetemperature of this shield by continually depositing their charges uponit. By proportioning the shield so that its radiating envelope iscomparable to that of the anode, account being taken of the positive ionheating effects, the shield can be made to operate at a 45 temperaturewhich is high in relation to that corresponding to the vapor pressure asdetermined by the cooled cathode and other condensing surfaces, at atemperature near that of the anode. By this arrangement, no condensa- 59tion in the form of vapor droplets occurs on the shield.

In order to prevent accumulation of non-condensable gases within theanode shield, I prefer to construct the shield with openings adjacent 55the top thereof and to permit the Working vapor (Cl. Z50-27.5)

of the device to sweep through the shield to clear the anode space ofany such foreign gases. -In order to prevent condensed mercury droppingthrough these openings into the vicinity of the anode, suitable shieldsare provided over the aforementioned openings.

It is accordingly an object of my invention to provide an electric valvehaving a hot shield interposed between the anode surfaces and thecondensing surfaces.

It is a further object of my invention to provide a shield structuremaintaining clean surfaces adjacent the anode space.

It is a further object of my invention to provide an electronic valve ofthe ignitron type having a metallic shield between the anode and thecooled side walls of the tube, said shield being maintained at hightemperature during operation of the valve by the heat losses of thevalve.

It is a further object of my invention to provide a shield structurewhich maintains the cooled vapors in a compartment separate from theanode space.

It is a further object of my invention to provide a shield structure inwhich the foreign gases will be eliminated from the anode space.

Other objects and advantages of my invention will be apparent from thefollowing detailed description taken in conjunction with theaccompanying drawings, in which:

y Figure 1 is a sectional elevation of a make- 30 alive type valveaccording to my invention, and

Fig. 2 is a similar view showing a modification according to myinvention.

In the illustrated embodiment of my invention according to Fig. l, thevapor electric device or valve comprises a container I, preferably ofmetal, having a suitable means such as a cooling coil 2 applied to theoutside thereof so that the surface of the container acts as a condenserfor the operating vapor of the device.

In the bottom of the container I is a suitable vaporizablereconstructing cathode 3, that is, the cathode 3 is comprised of amaterial which will evaporate to provide the working vapor of the deviceand which is condensed and returned to the cathode to maintain itsvolume substantially constant.

Cooperating with the cathode 3 is a suitable anode 4, preferablyconstructed of graphite, although any suitable material may be utilized,the anode being supported by a suitable conducting stem 5 which issealed to the container I by means of a suitable insulating bushing,herein illustrated as a porcelain bushing 6.

Q pendent upon its radiating surface.

A suitable make-alive type electrode 'l is supported in permanentcontact with the cathode 3.

Interposed between the anode 4 and the condensing surface is a suitableshield ill preferably of metal. The shield IE! may be supported in anydesired manner, but I prefer to support the shield ill on the insulatingbushing 6 surrounding the anode stem and to provide openings Il adjacentthe upper portion of the shield Il) so that vapor from the cathode 3 maypass through the anode space and out through the openings Il to thecondensing surface.

To prevent condensed mercury or other material from entering the anodespace through these openings Il, a suitable shield I2 is interposed inspaced relation to these openings Il and so positioned that any materialfalling or projected toward the openings will be deected into the spacebetween the shield i0 and the condensing surface.

Preferably, l0 is projected into the shield proximity with or even. intocontact with the vapor flow will carry the non-condensing gases.

Preferably, the shield lil is cut away to provide an opening l for theinsertion of the makealive electrode 'l so that the device may beassembled or disassembled without disturbing the make-alive connection.

However, as shown in Fig. 2, the make-alive electrode 'l may bepermanently connected to a portion of the shield structure, andconnection made thereto by a suitable conductor l1 having a springcontact i8 on the shield surface. When the make-alive electrode'l isconnected to the shield structure, it is necessary to provide sufcientdistance between the bottom of the shield l] and the cathode surface toprevent accidental grounding of the shield HJ by the agitation of themercury surface during operation of the device.

In the operation of my device, the anode d will operate at an elevatedtemperature, since substantially the entire heat energy generated at theanode surface must be dissipated by radiation. A portion of the energywill be radiated tothe shield l0 and will raise it to a temperatureapproaching that of the anode surface. Since the shield if! too mustlose its energy substantially by radiation because of the thermal heatinsulation provided by the porcelain support B, the temperature of theshield i0 is substantially de- Therefore, the shield lll having a largerradiating area than the anode ll and receiving energy substantially onlyfrom the anode 4 will in'most designs nrmally operate at an elevatedtemperature nearer that of the anode 4 and intermediate between that ofthe anode 4 and the condensing surface. Since the shield lll isconstantly in a heated condition during operation, the working vaporsweeps through the anode space carrying with it any foreign gases thatmay be present. In this way, the surfaces exposed to the anode 4 duringoperation will remain substantially clean and free of condensedmaterial. Any condensed material will tend to be maintained in the spacebetween the shield I0 and the condensing surface.

In the modification according to Fig. 2, the

openings 20 are shielded by straps 2| spaced from and secured across theopenings 20 instead of by a sloping annular shield l2 as in Fig. 1. Themake-alive electrode 1 is shown supported directly fromA the shieldstructure Ill and a conductor having a suitable resilient connection I8contacting with a portion of the shield surface. v

While for purposes of illustration I have shown and described specificembodiments of my invention, it will be apparent to those skilled in theart that many changes and modifications can be made therein withoutdeparting from thetrue spirit of my invention or the scope of theappended claims.

I claim as my invention:

1. A single anode vapor-electric device comprising an anode, acooperating vaporizing cathode, an evacuated metallic chamber enclosingsaid anode and cathode, the side Walls of said chamber being in closeproximity to the anode, a shield substantially enclosing the anode andextending adjacent the cathode, a makealive electrode for initiating acathode spot on said cathode within the confines of the shield,

vapor passages in said shield adjacent the topv of the anode and meansfor supporting said shield in thermal and electrical insulated relationto said anode and said chamber. v

2. A vapor-electric device comprising an evacuated metallic container, avaporizable cathode in said container, a single anode cooperating withsaid cathode, means for cooling the side walls of said container, ashield intery HERBERT A. ROSE.

